Conventionally a contact lens-type display device is proposed as a wearable device that is wearable on an eye of a user (e.g. see Patent Literature 1). Since the display device is worn on an eyeball of the user and is used wirelessly, the user can make movements such as freely walking around in a state of wearing the display device.
There are also a head mount display, an eyeglass-type display, etc. as wearable devices that are worn around the eye, such as on the head of a user.
In these wearable devices, electricity supply to each part is performed by a battery provided in the wearable device.